USMLE PEARLS PART 2

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Ectopic Pregnancy

 

v     Most ectopics are found in the fallopian tube, although they can occasionally occur at other pelvic sites.

v     If a tubal pregnancy is allowed to continue, it may eventually rupture the fallopian tube and cause life threatening haemorrhage.

v  Early diagnosis and treatment is, therefore, important, and may even allow the tube to be saved.

 

The Symptoms

Initially an ectopic pregnancy may appear just as a normal pregnancy –

with a missed menstrual period and symptoms such as sore breasts and nausea.

However, there is often abnormal vaginal bleeding which may occur at the time of (or a little later than) the expected period, and may, in fact, be mistaken for a period.

Pain on the side of the ectopic occurs commonly and may be associated with a feeling of light-headedness or a desire to use one's bowels.

If the tube ruptures, this usually results in severe abdominal pain and fainting. EVEN SHOCK

Early stages: 1. Lower abdominal cramps. 2. Missed menstrual period or a heavy, painful period. 3. Unexplained vaginal spotting or bleeding. 4. Pain in the shoulder (rare). Late stages: 1. Sudden, sharp, severe abdominal pain caused by rupture of the fallopian tube. 2. Dizziness, fainting and shock (paleness, rapid heartbeat, drop in blood pressure and cold sweats)    These may precede or accompany pain (sometimes).

 

Who Is At Risk?

Ectopic pregnancy occurs once in every one hundred pregnancies. However, some women have a slightly higher risk than this. Important risk factors are:

• An intrauterine device (IUD)
• The "morning after" pill
• The progesterone only or "mini" pill
• Tubal damage caused by infection
• Tubal surgery, e.g. tubal ligation or sterilisation reversal
• IVF and GIFT
• A previous ectopic pregnancy.

Women who are at increased risk may be advised to have an ultrasound scan in early pregnancy, particularly if they have any vaginal bleeding.

·         Pelvic inflammatory disease ·         Previous tubal pregnancy (repeat rate is about 12%) ·         History of Endometriosis ·         Previous tubal surgery ·         Multiple induced abortions ·         Pelvic adhesions (bands of scar tissue that constrict the tube, most often a result of pelvic surgery) ·         Use of medications to stimulate ovulation < ·         Use of an intrauterine device (IUD)—primarily because of the risk of scaring

 

 

	Diagnosis and Treatment
	General Measures ·                    A pregnancy test will be run (if the pregnancy has not already been confirmed). ·                    Blood levels of HCG will be evaluated. Human chorionic gonadotropin is a hormone that is present in a woman’s system during pregnancy. In a normal pregnancy, HCG levels doubles about every two days ·                    during the first 10 weeks of pregnancy. In an ectopic pregnancy, though, the HCG level climbs significantly more slowly. This difference helps distinguish between a normal and an ectopic pregnancy. A physician may run HCG tests over a period of days to examine the pattern of increase. Serial serum B-hCG testing: -ELISA method - a quantative measurement which measures the serum B-hCG -Results can be used to detect pregnancy; monitor the progress; help in establishing the estimated gestational age; detect levels of HCG which can occur in conditions not related to pregnancy, ex: gestational trophoblastic disease Results reported in mIU/ml (milliInternational units per milliliter) Rate of B-hCG rise in serum in a normal pregnancy: -doubles every two days -detectable within 24-48 hours after implantation -peaks in 10 weeks after last menstrual period Ectopic pregnancy is associated with an impaired HCG production an increase in serum B-hCG less than 66% over two days is predictive of ectopic pregnancy Correlate lab results with the clinical picture to establish the diagnosis ·                      ·                    Blood levels of Progesterone may be evaluated. Progesterone levels are high during pregnancy. In an ectopic pregnancy, progesterone levels are lower than during a normal pregnancy. ·                    An ultrasound will be done to determine if the uterus contains a developing fetus. The ultrasound allows the doctor to visualize the uterus and ovaries from outside the body. The ultrasound may be done abdominally or vaginally. ·                    Occasionally, culdocentesis is done. In culdocentesis, a needle is inserted at the top of the vagina, between the uterus and the rectum, to check for blood. The presence of blood may indicate bleeding from a ruptured fallopian tube.
	TO RESUME EXPLORATION
	Diagnostic tests may include blood tests,  serum pregnancy test [HCG] , ultrasound,  culdocentesis, laparoscopy, D & C (dilation and curettage)  and exploratory laparotomy.
	* Hospitalization may be required for surgery and supportive care. Blood transfusion may be necessary.
	Surgery to remove the developing fetus, the placenta, and any damaged tissue.  If the fallopian tube cannot be repaired, it is removed.  Future normal pregnancy is possible with one fallopian tube.
	Medication
	Pain-killers after surgery may be prescribed.
	Activity
	Resume normal activities,  including sexual relations, as soon as possible.  Frequent, satisfying sexual activity helps feel closer to your mate and promotes healing.
	Diet
	No special diet.
	Possible Complications
	1. Diminished fertility.
	2. Infection.
	3. Loss of reproductive organs after complicated surgery.
	4. Shock and death from internal bleeding.
	Prognosis
	v     An ectopic pregnancy cannot progress to full term or produce a viable fetus. v     Rupture of an ectopic pregnancy is an emergency, requiring immediate hospitalization and surgery. v     Full recovery is likely with early diagnosis and surgery. v     Subsequent pregnancies are usually normal in about 88% of patients.
v  A 30-year-old woman presents to the emergency room with abdominal cramping and vaginal bleeding. Her last menstrual period was 7 weeks ago. Physical examination reveals a palpable left adnexal mass. She has a positive pregnancy test with beta-HCG (human chorionic gonadotropin) of 14,000 IU/L. Which study do you request first? Plain abdominal radiographs Abdominal-pelvic CT Pelvic MRI Pelvic ultrasound Hysterosalpingography 4/ Endovaginal ultrasound shows no intrauterine pregnancy. There is a gestational sac adjacent to the left ovary (LO) containing a yolk sac fetal pole and fetal heart The fetal heart rate is 139 bpm. A small amount of free fluid is visible in the cul-de-sac These findings are diagnostic of a left ectopic pregnancy. Algorithm for Ectopic Pregnancy Pelvic ultrasound Note: Normal pelvic ultrasound does not exclude an ectopic pregnancy. Patient should be followed with serial beta-HCG levels and repeat ultrasound if indicated   Ectopic pregnancy occurs in 1:100-400 pregnancies and accounts for 15% of maternal deaths. The only sonographic finding that reliably excludes an ectopic pregnancy is a demonstration of an intrauterine pregnancy since concomitant presence of an intrauterine and an extrauterine pregnancy is extremely rare (except in induced ovulation). Endovaginal ultrasound can detect a living embryo in 30% of ectopic pregnancies. Presence of an adnexal mass and/or cul-de-sac fluid in a patient with no intrauterine gestation and measurable circulating human chorionic gonadotropin (HCG) are highly specific for the diagnosis of ectopic pregnancy. However, absence of these findings does not exclude the diagnosis since up to 30% of women with extrauterine gestations have no sonographic evidence of an adnexal mass or pelvic intraperitoneal fluid. A pseudogestational sac (decidual reaction and anechoic fluid collection in the endometrial cavity) can be seen in 10-20% of ectopic pregnancies and should not be confused with an intrauterine gestation. Ninety-five percent of ectopic pregnancies occur in the fallopian tubes. Ovarian, abdominal, cervical and interligamentary ectopics are rare.

 

COMPLICATION OF PREGNANCY

Ectopic Pregnancy
Incompetent Cervix
Miscarriage
Placenta Praevia
Placental Insufficiency
Placental Separation
Pre-Eclampsia & Eclampsia
 

Incompetent Cervix [DETAILS WILL BE ON OTHER WEB PAGES USMLE RELATED]

  In normal pregnancy, the cervix is sealed closed with a plug of mucus, which holds the foetus in the uterus

   In an incompetent cervix, the cervix may begin to open before the term of the pregnancy (usually in the third of fourth month).

  This leads to rupture of the amniotic sac and miscarriage follows.

  This condition is rare, but may occur if the cervix has been damaged during previous pregnancies or surgery.

   This condition is not usually diagnosed until a first miscarriage has occurred.

  If a previous miscarriage is thought to have been caused by an incompetent cervix, preventative measures can be taken for your next pregnancy. Rest is recommended.

Miscarriage [DETAILS WILL BE ON OTHER WEB PAGES USMLE RELATED]

  The loss of a baby before 28 weeks is termed a miscarriage while after 28 weeks, loss of the foetus is called a stillbirth.

  There are many known causes of miscarriage, and some unknown causes.

  Miscarriages usually occur in the first trimester, sometimes before the pregnancy has even been suspected or diagnosed.

  In the first few weeks of pregnancy approximately 30% of all pregnancies end in miscarriage.

  In some cases a period may be late and heavy and the conception and miscarriage may not even have been realised.

   When a couple experiences a miscarriage, they are still likely to conceive again, however miscarriages can increase in frequency with age and with the number of previous pregnancies.

  Small numbers of women can experience up to three or more miscarriages in a row and approximately 50% of these women may still go on to have a successful pregnancy, even though they will have suffered emotional pain, frustration and disappointment on previous occasions.

   If bleeding occurs at any stage in your pregnancy you must see your doctor. Bleeding is the most common symptom of miscarriage.

  Miscarriage can be caused by many factors including:

  ·Genetic problems due to chromosomal defects

  ·Environmental factors such as smoking,

  alcohol and other recreational drugs

  ·Hormonal abnormalities

  ·Pre-existing disease or illness,

   uterine abnormalities or other medical conditions in the womb ·

  Bacterial and viral infections

   While most people generally understand the need to grieve for the loss of a stillborn baby (after 28 weeks), often others do not understand that a miscarriage can also cause grief and depression

Placenta Praevia [DETAILS WILL BE ON OTHER WEB PAGES USMLE RELATED]

  In a normal pregnancy the placenta implants itself in the top part of the uterus.

  In placenta praevia the placenta implants itself in the lower part or on the side of the uterus and can get in the way of the baby’s passage at birth.

  The cause of placenta praevia is unknown, but it is more common in women who have had several children.

  Symptoms are bleeding after the 20th week of pregnancy (possibly after sex) and haemorrhage in the last two months of pregnancy.

  Placenta praevia can be diagnosed by ultrasound and treatment involves bed rest.

Placental Insufficiency [DETAILS WILL BE ON OTHER WEB PAGES USMLE RELATED]

  A healthy placenta is vital for maintaining a healthy baby.

  An insufficient placenta can prevent your baby from gaining essential nourishment.

   Symptoms for placental insufficiency may include

   below average weight gain,

  below average fetal development,

   or slow growth of the uterus.

  An ultrasound examination will determine if growth of the fetus is adequate.

  Another useful sign is the activity of the baby in the last few months of pregnancy.

Placental Separation [DETAILS WILL BE ON OTHER WEB PAGES USMLE RELATED]

  Sometimes the placenta can separate from the uterus, either partially or completely.

  This is more common in women who have had more than two children, but the cause is unknown.

   In mild cases, slight blood loss occurs and the condition is treated with bed rest and monitored by ultrasound, however labour may be induced if the pregnancy is close to term.

  The condition is acute when more blood is lost and a large amount of the placenta separates from the wall

Pre-Eclampsia & Eclampsia [DETAILS WILL BE ON OTHER WEB PAGES USMLE RELATED]

  Pre-eclampsia is a form of high blood pressure induced by pregnancy and occurrs in approximately 15% of pregnancies.

  The condition relates to the health of the placenta and is more likely to occur in first time pregnancy’s, women over 35, multiple pregnancy’s, severely obese women or women who have suffered from pre-eclampsia in a previous pregnancy.

  Symptoms can include:

   increasing blood pressure,

  protein in the urine,

  disturbances in kidney

  and liver function,

  fluid retention,

  swelling of face,

  hands and feet and possibly headaches,

  dizziness and nausea.

 

TRAUMA AND NEURO:

  Acute epidural hematomas generally result from trauma to the side of the head with fracture of the temporoparietal bone and severance of the middle meningeal artery, which lies between the dura and the inner table of frontal bone.

  Arterial bleeding in an epidural hematoma creates a potential space between the calvarium and dura, thus producing a true epidural compartment.

  Typically, the patient is initially rendered unconscious and then regains consciousness (lucid interval). After 4 to 8 hours, when there is approximately 30 to 50 ml of blood in the space, the patient develops evidence of raised intracranial pressure (e.g., papilledema, convulsion) and may die of herniation unless the blood is surgically removed. There is a 20% mortality rate.

  Subarachnoid and intracerebral hemorrhages are not associated with trauma.

  Subdural hematomas are most common in elderly individuals and chronic alcoholics who have cerebral atrophy.

DETAILS AND CASES:

• Young men (20-40's)
• Acute presentation
• Skull fracture (90%)
• Bi-convex, hyperdense- limited by sutures

• Significant trauma
• Fracture & concussion (l.o.c.)
• Wakes up (lucid interval - 40% pts.)
• Delayed neurologic Sx (hrs. Later)
• Herniation, coma and death

• Trauma -> fracture & concussion
• Tearing/stripping of both layers from inner table
• Laceration of outer periosteal layer
• Laceration of meningeal vessels
• Inner (meningeal dura) intact
• Blood between naked bone and dura

 

SOURCE OF BLEEDING

• MENINGEAL VESSELS
  • Arterial (high pressure)
  • Venous (low pressure)
• DURAL SINUS
  • High flow, low pressure
• OTHER
  • Diploic veins (Fx)
  • Marrow sinusoids

blood vessels tear, blood accumulates within the space between the dura and the skull.

 This is known as an epidural hematoma (epi-door-ul hem-a-to-ma), or blood clot at the covering of the brain.

When the blood accumulates between the dura and skull, swelling of the brain occurs.

There is no extra room within the skull to allow for the brain to swell and for the blood to accumulate.

The only way the brain can compensate is to shift the delicate structures out of the way.

 This can cause pressure on vital functions, such as eye opening, speech, level of awakeness (or consciousness) or even breathing.

Generally, an epidural can cause serious problems and must be removed to prevent increased swelling of the brain.

The procedure of choice for removal of an epidural hematoma is surgery to remove the blood clot.

Causes

An epidural hematoma can happen to anyone, at any age. Some common causes of epidural hematoma include:

• A blow to the head, such as in a motor vehicle crash, assault or bicycle accident
• Falling down and striking the head

People at particular risk are those who:

• Are elderly and have trouble walking or fall often
• Take a blood thinner, such as Coumadin

Signs and symptoms

The signs and symptoms of an epidural hematoma include

  severe headache,

  dizziness,

  vomiting,

  increased size of one pupil or sudden weakness in an arm or leg.

  As the epidural hematoma swells and the brain structures are pushed together, more visible signs can occur.

  A more dangerous sign of epidural hematoma is a decreased level of consciousness, such as drowsiness, confusion or inability to awaken from a very deep sleep (often called coma).

  Because the brain controls all functions of the human body, breathing pattern changes also can occur.

  Shortness of breath, gasping for air or very slow breathing can be a warning sign that the person needs help.

  An epidural hematoma can be life-threatening; therefore, if any of these signs or symptoms occur, the person should be taken to a medical facility immediately.

• incidence: 5% of head trauma patients
• age: infants and elderly (large subarachnoid space with freedom to move)
• cause: damage to subdural veins ("bridging veins")
• acute subdural hematoma:
  • manifests hours after injury
  • hyperdense (<1 week); isodense (1-3 weeks); hypodense (3-4 weeks)
  • underlying brain injury (50%)
  • worse long term prognosis than epidural hematoma
• chronic subdural hematoma
  • following minor injury; rarely parenchymal injury
  • convex configuration (unlike acute subdural)
• interhemispheric subdural hematoma
  • most common acute finding in child abuse (whiplash injury)
  • predominace for posterior portion of interhemispheric fissure

 

a 47 year old right-handed construction worker who slipped off a ladder and fell from a height of 8 feet. He landed on his left side, striking his head. He denies loss of consciousness, but he did feel "groggy". He was taken by ambulance to the Bellevue Hospital Emergency Room.

On exam, the patient was alert and oriented. He recalled the details of the event. He was neurologically intact. He had a 3 cm scalp laceration in the left parietal region. Within several minutes of his arrival, however, he complained of severe headache and vomited.

Radiographic Studies

Click on an image to see full size.

The CT scans above show subarachnoid hemorrhage over the right cerebral convexity and in the Sylvian fissure. In addition, there is a small, less than 1 cm thick left temporal epidural hematoma. The bone windows show an overlying temporal bone fracture.

Impression

The patient's acute epidural hematoma located in the temporal region was felt to be a life-threatening problem, requiring immediate surgical intervention. Although the patient was neurologically intact and alert, this lesion has the potential to cause uncal herniation and rapid deterioration or death without warning. In addition, the overlying pterional fracture suggests a laceration of the middle meningeal artery, with the probability that the hematoma will continue to expand.

The subarachnoid hemorrhage is probably traumatic in etiology. It is located over the convexity and there is no basilar cistern subarachnoid blood. The patient clearly gave a history of slipping on the ladder rather than experiencing symptoms which may have caused the fall, such as headache or loss of consciousness. Therefore the possibility of an aneurysm is low.

Operative Procedure

The patient underwent a left temporal craniotomy and evacuation of the epidural hematoma. The skull fracture noted on the CT was encountered. The middle meningeal artery was lacerated in 2 separate locations and was actively bleeding. The dura was tacked up the the bone edges. Intraoperative ultrasound was used to be sure that no contusions or subdural hematomas had formed since the time of the CT scan, and this looked normal. The contralateral side was not visualized due to the limitations of the intraoperative ultrasound technique. We considered leaving an intracranial pressure monitor, but because the patient was alert and intact preoperatively we decided to observe his neurologic exam instead.

Postoperative Course

In the Recovery Room, the patient was somnolent but aroused to voice and followed complex commands. Because of the somnolence, and because of the underlying right hemisphere diffuse injury, we had a low index of suspicion for progression of further injuries, and a CT scan was obtained.

The scan above deomonstrates a large intracerebral hematoma in the right temporal lobe, with mass effect and impingement of the uncus on the lateral brainstem suggesting impending herniation. The left epidural hematoma has been satisfactorily evacuated. At this time the patient had no third nerve palsy or hemiparesis. The operating room was immediately mobilized and Mannitol was given.

Second Operative Procedure

A right frontotemporal craniotomy and partial anterior inferior temporal lobectomy were performed. We encountered frank hematoma as well as severely contused and necrotic temporal tissue, which were removed. The temporal lobectomy extended from the upper border of the middle temporal gyrus superiorly, medially just 0.5 cm short of the tentorial incisura, and posteriorly 5 cm from the temporal pole. At the conclusion of the procedure the brain was relaxed and pulsing well.

Outcome

Postoperatively, the patient was again somnolent but following complex commands and nonfocal. CT showed resolution of mass effect and the lobectomy cavity. He continued to improve and within 24 hours was alert and neurologically intact. Visual fields were intact on formal ophthalmological testing. He was discharged home on the 7th postoperative day

A 31-year-old woman was brought to the emergency room by an ambulance after being struck by a car. She was initially responsive at the scene but subsequently lost consciousness and had to be intubated. Her vital signs were stable and preliminary examination did not show any sign of abdominal injury or open fractures. Her pupils were equal and reactive and she responded to painful stimuli. Portable radiographs of the chest and lateral cervical spine were unremarkable.

Imaging Findings

Noncontrast CT of head

Computed tomography (CT) of the head obtained without intravenous contrast enhancement shows a biconvex high-attenuation epidural hematoma adjacent to the right frontal lobe The lesion extends superiorly to the level of the body of the lateral ventricle and inferiorly to the roof of the right orbit Mild mass effect is exerted on the subjacent brain parenchyma. A fracture is visible extending through the right side of frontal bone to the roof of the right orbit with associated extracranial soft tissue swelling

Diagnosis

epidural hematoma

Discussion

Epidural hematomas are seen in 1-4% of patients with intracranial trauma but they account for 10% of fatal injuries. Laceration of the middle meningeal artery or a dural venous sinus by a skull fracture is responsible for 85-95% of patients with epidural hematomas; the remainder have venous bleeding or middle meningeal artery tear without a fracture. Ninety-five percent of epidural hematomas are unilateral and supratentorial, commonly occurring in the temporoparietal area. They are located between the skull and dura and have a characteristic biconvex or lentiform configuration on CT scans. Two thirds of acute epidural hematomas are hyperdense on CT; one third contain hypodense areas secondary to active bleeding. The overall mortality with epidural hematomas is 5%, and poor outcome is often due to delayed diagnosis or late surgical intervention.

 

 

Epidural hematoma: A 20-year-old man presented with a brief loss of consciousness following a fall from standing height. He had a brief lucid interval then became progressively less responsive. A computed tomography scan of the head reveals effacement of the third ventricle, quadrigeminal cistern, and compression of the anterior and posterior horns of the lateral ventricle. A lenticular-shaped hyperdense area consistent with an acute epidural hematoma is seen on the right. (L.S.)

A 36-year-old man with a history of alcohol abuse presented with left-sided weakness and memory loss.

Imaging Findings

Computed Tomography

Axial CT images of the brain show a large isodense right-sided subdural hematoma extending from the high convexities to the low frontal lobe. It is producing extensive right to left midline shift with subfalcine  and right uncal  herniation. There is trapping of the ventricles and left temporal horn with acute ependymal cerebrospinal fluid seepage, predominantly in the left periatrial and occipital regions .

Cerebral and cerebellar atrophy is also present. Note the difference in the sulci of the two hemispheres.

Differential Diagnosis

The main differential considerations include subdural and epidural hematoma. Epidural hematomas (EDH) form in the space between the dura and the inner table of the skull. Unlike subdural hematomas, EDH can cross the midline, but will not cross the cranial sutures where the dura is firmly attached. The subdural hematoma (SDH), however, may freely cross the midline insertion of the falx or the tentorial attachment. Also in comparison to SDH, EDH is often associated with skull fractures (85 - 95% of adult cases) which disrupts the middle meningeal artery, resulting in a lenticular or biconvex extra-axial collection.

Subarachnoid hemorrhages can be distinguished radiographically from SDH by their extension into cerebrospinal fluid space, and appearance on CT as linear areas of high attenuation within the cisterns and sulci.

Diagnosis

Subacute subdural hematoma.

Discussion

Subdural hematoma (SDH) is the most common extra-axial collection and is seen in 5% of head trauma patients. SDH occurs between the dura and the arachnoid membrane, most often due to venous bleeding from the "bridging" subdural veins which connect the cerebral cortex to the dural sinuses. However, SDH may also result from disruption of the penetrating branches of superficial cerebral arteries. These ollections tend to conform to the shape of the brain and the cranial vault, exhibiting concave inner margins and convex outer margins. Occasionally, SDH may be straight or even concave in appearance.

Patients with SDH commonly present after acute deceleration injury from a fall or motor vehicle accident, but are rarely associated with skull fracture. More rarely, coagulopathies, tumors, or aneurysms may be responsible for SDH.

SDH may be classified as hyperacute (low density) if less than 12 hours from the acute event, acute (high density) if less than few days, subacute (isodense) from a few days to 2-3 weeks, and chronic (low density) if more than 3 weeks after the time of injury.

A 75-year-old man was brought to the emergency room by his family because of an acute change in his mental status. He had reportedly fallen at home the evening before but did not have any complaints at that time. On exam, he was disoriented to place and time but had no focal neurologic deficit. His laboratory values were unremarkable. Plain films of the cervical spine showed degenerative spondylosis but no fracture.

Imaging Findings

Noncontrast CT of the head

Computed tomography without intravenous contrast enhancement indicates a crescentic hyperdense right subdural hematoma extending from the skull base to the high convexity The subdural collection extends into the interhemispheric fissure anteriorly There is a minimal compression of the body of the right lateral ventricle Soft tissue swelling is present over the left parietal region but no fracture is evident

Diagnosis

Subdural hematoma

Discussion

Subdural hematomas are seen in 10-20% of patients with intracranial trauma and account for 30% of fatal injuries. The most common etiology of subdural hematomas is stretching and tearing of bridging cortical veins in the subdural space due to sudden change in velocity of the head. A definite history of trauma may be absent, especially in elderly patients. Subdural hematomas occur between the dura and arachnoid. The characteristic CT appearance of an acute subdural hematoma is a crescentic, hyperdense extraaxial collection that spreads diffusely over the affected hemisphere. Subdural hematomas commonly occur over the frontoparietal convexities and in the middle cranial fossa. Subdural hematomas undergo clot lysis and organization over time. Within a few days to a few weeks after trauma, subacute subdural hematomas become nearly isodense with the underlying brain parenchyma. Chronic subdural hematomas are typically low attenuation. In 5% of cases, recurrent hemorrhage into a preexisting chronic subdural hematoma produces a mixed density collection. Mortality rates from a traumatic acute subdural hematoma is very high, ranging from 50 to 85%.

 

1 year old male with mental status changes

Imaging Technique

CT

Imaging Findings

Left occipital skull fracture extending thru the skull base to the spheno-occipital fissure. Large epidural occipital hematoma with compression of the fourth ventricle - hydrocephalus.

Diagnosis

Basilar Skull Fracture-Epidural Hematoma

Discussion

A subdural and epidural hematoma may be differentiated from one another in that an epidural hematoma, as in this case, can cross falcine boundaries/ dural boundaries. However, it will not cross suture line (vice versa). Most commonly, occipital epidural hematomas are secondary to venous sinus injury. However, it may also result from injury to a branch of the posterior meningeal artery. This patient's lack of history of significant trauma is incongruous with the above findings raising a suspicion of non-accidental trauma. head trauma is the leading cause of morbidity and mortality in the abused child (esp. under the age of 2). Manifestations of injury include SDH (most common, often chronic), SAH, cerebral contusion and DAI (often in the "shaken baby") as well as contre-coup injury. Skull fractures are seen in 45% of affected children. Multiple fractures, stellate fractures, bilateral fractures, depressed fractures and fractures which are > 5 mm wide at presentation should raise a suspicion of NAT. MRI may be useful in recognizing intracranial bleeds of differing ages. Common presentations include that of an irritable or abnormally subdued child or seizures.

 

 

After brain injury, the contents may change. The brain tissue may swell, causing it to take up more room in the skull. This is called edema. When this occurs, the swollen brain tissue will push the other contents to the side.

Brain with Edema

There may be bruising called contusions or a collection of blood called a hematoma or clot. This may also push the other contents to one side.

Brain with a Hematoma

The flow of CSF may also become blocked. This will cause the open spaces (ventricles) to become enlarged. This is called hydrocephalus.

Brain with Hydrocephalus

Every injury is different. Most injuries are a result of bruising, bleeding, twisting, or tearing of brain tissue. Damage to the brain may occur at the time of injury. It may also develop after the injury due to swelling or further bleeding. Patients may have more than one type of brain injury.

Skull Fracture:
a break in the bone that surrounds the brain. These fractures often heal on their own. Surgery may be needed if there has been damage to the brain tissue below the fracture.

Contusion/Concussion:
a mild injury or bruise to the brain which causes a short loss of consciousness. It may cause headaches, nausea, vomiting, dizziness, and trouble remembering or concentrating. This injury will not need surgery.

Coup-Contra Coup:
A French word that describes contusions that occur at two sites in the brain. The force of the impact causes the brain to bump the opposite side of the skull. Damage occurs at the site of impact and on the opposite side of the brain.

Epidural Hematoma:
A blood clot that forms between the skull and the top lining of the brain (dura). This blood clot can cause fast changes in the pressure inside the brain. Emergency surgery may be needed. The size of the clot will determine if surgery is needed.

Subdural Hematoma:
A blood clot that forms between the dura and the brain tissue. If this bleeding occurs quickly it is called an acute subdural hematoma. If it occurs slowly over several weeks, it is called a chronic subdural hematoma. The clot may cause increased pressure and may need to be removed surgically.

Intracerebral Hemorrhage:
A blood clot deep in the middle of the brain that is hard to remove. Pressure from this clot may cause damage to the brain. Surgery may be needed to relieve the pressure.

Diffuse Axonal Injury (DAI):
Damage to the pathways (axons) that connect the different areas of the brain. This occurs when there is twisting and turning of the brain tissue at the time of injury. The brain messages get slowed or lost. Treatment is aimed at managing swelling in the brain because torn axons can not be repaired.

Anoxic Brain Injury:
An injury that results from a lack of oxygen to a part of the brain. This is most often from a lack of blood flow due to injury or bleeding. This will cause swelling of the brain tissue.

 

Any of these changes can cause increased intracranial pressure.

Patients with brain injury require frequent assessments and diagnostic tests. These include:

·  Neurological Exam: A series of questions and simple commands to see if the patient can open their eyes, move, speak, and understand what is going on around them. For example: What is your name? Where are you? What day is it? Wiggle your toes. Hold up two fingers.

·  X-ray: A picture that looks at bones to see if they are broken (fractured). It can also be used to take a picture of the chest to look at the lungs. This test may be done at the bedside or in the X-ray department and takes between 5-30 minutes to complete.

·  CT Scan (CAT Scan): A X-ray that can take pictures of the brain or other parts of the body. The scan is painless but the patient must lie very still. The test takes 30-60 minutes to complete.

·  MRI (Magnetic Resonance Imaging Scan): A large magnet and radio waves are used, instead of X-rays, to take pictures of the body's tissues. It is painless but noisy. The machine is shaped like a long tube. The patient must lie on a flat table in the middle of the machine. The test takes about 60 minutes to complete.

·  Angiogram: A test to look at the blood vessels in the brain. Dye is put into a catheter in an artery (usually in the groin) that supplies blood to the brain. This test can tell if the arteries or veins have been damaged or are spasming. The test takes 1-3 hours.

·  ICP Monitor: A small tube placed into or just on top of the brain through a small hole in the skull. This will measure the pressure inside the brain (intracranial pressure).

·  EEG (Electroencephalograph): A test to measure electrical activity in the brain. Special patches called electrodes are applied to the head to measure the activity. The test is painless and can be done at the bedside or in the EEG department. The length of the test varies.

 

 

  Carpal tunnel syndrome is caused by compression of the median nerve at the level of the wrist.

  The median nerve supplies sensation to the radial 3 1/2 digits of the hand as well as innervation of the thenar musculature.

  Symptoms include numbness and tingling in the fingertips and pain that can awaken the patient at night and that can travel proximally up the arm.

  On physical examination, Tinel's sign and Phalen's test are usually positive, and there can be sensory loss in the median nerve distribution and muscle weakness.

  Pronator syndrome is a median nerve entrapment in the proximal forearm. It is a pure sensory syndrome. The Phalen's test is negative.

  The cubital tunnel is a groove in the posteromedial aspect of the elbow that contains the ulnar nerve.

  Cubital tunnel syndrome is an ulnar nerve neuropathy.

  Ulnar nerve entrapment can occur at the wrist in Guyon's canal. In both of these conditions, patients may complain of numbness in the ulnar 1 1/2 digits and have weakness of the intrinsic muscles.

  De Quervain's disease is usually caused by repetitive use of the thumb for some activity. Patients have pain and tenderness at the region of the radial styloid.

Olympic cyclist is seen in the orthopaedic clinic with complaints of numbness in her fingertips and pain in her left hand that occasionally radiates up her arm. She is often awakened by the symptoms.

On physical examination, there is decreased sensation over the radial 3 1/2 digits of the hand and the Phalen's test is positive  =Carpal tunnel syndrome