Hydrocephalus PDF

HYDROCEPHALUS APPLIED PATHOLOGY  LEARNING OBJECTIVES IN THIS TOPIC WE WILL LEARN ABOUT HYDRONEPHROSIS AND ALSO ABOUT ITS CAUSES, PATHOPHYSIOLOGY AND RISK FACTORS. WILL DISCUSS ABOUT ITS COMPLICATIONS AND INVESTIGATIONS.  OVERVIEW THE TERM HYDROCEPHALUS...

HYDROCEPHALUS APPLIED PATHOLOGY  LEARNING OBJECTIVES IN THIS TOPIC WE WILL LEARN ABOUT HYDRONEPHROSIS AND ALSO ABOUT ITS CAUSES, PATHOPHYSIOLOGY AND RISK FACTORS. WILL DISCUSS ABOUT ITS COMPLICATIONS AND INVESTIGATIONS.  OVERVIEW THE TERM HYDROCEPHALUS IS DERIVED FROM TWO WORDS: "HYDRO" MEANING WATER, AND "CEPHALUS" REFERRING TO THE HEAD. HYDROCEPHALUS IS A CONDITION IN WHICH EXCESS CEREBROSPINAL FLUID (CSF) BUILDS UP WITHIN THE VENTRICLES (FLUID-CONTAINING CAVITIES) OF THE BRAIN AND MAY INCREASE PRESSURE WITHIN THE HEAD. ROUTE OF CSF  FUNCTIONS OF CSF CSF HAS THREE CRUCIAL FUNCTIONS: I. IT ACTS AS A "SHOCK ABSORBER" FOR THE BRAIN AND SPINAL CORD II. IT ACTS AS A VEHICLE FOR DELIVERING NUTRIENTS TO THE BRAIN AND REMOVING WASTE III. IT FLOWS BETWEEN THE CRANIUM AND SPINE TO REGULATE CHANGES IN PRESSURE WITHIN THE BRAIN.  HYDROCEPHALUS OCCURS WHEN THERE IS AN IMBALANCE BETWEEN THE AMOUNT OF CSF THAT IS PRODUCED AND THE RATE AT WHICH IT IS ABSORBED. AS THE CSF BUILDS UP, IT CAUSES THE VENTRICLES TO ENLARGE AND THE PRESSURE INSIDE THE HEAD TO INCREASE. HYDROCEPHALUS CAN OCCUR AT ANY AGE, BUT IS MOST COMMON IN INFANTS AND ADULTS AGE 60 AND OLDER.  TYPES OF HYDROCEPHALUS OBSTRUCTIVE HYDROCEPHALUS NON-OBSTRUCTIVE HYDROCEPHALUS CONGENITAL HYDROCEPHALUS AQUIRED HYDROCEPHALUS  TYPES... 1. NON OBSTRUCTIVE: ALSO KNOWN AS COMMUNICATING HYDROCEPHALUS OCCURS WHEN THE CSF FLOWS OUT OF THE CHAMBERS OF THE BRAIN (VENTRICLES) AND INTO THE SPINAL CANAL, BUT IT IS NOT REABSORBED NORMALLY BY THE TISSUE SURROUNDING THE BRAIN AND SPINAL CORD. SOMETIMES THIS TYPE OF HYDROCEPHALUS CORRECTS ITSELF. 2. OBSTRUCTIVE : OR NON COMMUNICATING, HYDROCEPHALUS OCCURS WHEN THE CSF DOES NOT FLOW PROPERLY BETWEEN OR OUT OF THE BRAIN VENTRICLES BECAUSE OF AN OBSTRUCTION, SUCH AS FROM A MALFORMATION OR NARROWING. 3. CONGENITAL: IT RESULTS FROM A COMPLEX INTERACTION OF GENETIC AND ENVIRONMENTAL FACTORS AND IS PRESENT AT BIRTH. OFTEN THE EXACT CAUSE OF CONGENITAL HYDROCEPHALUS CANNOT BE DETERMINED.  THOUGH IT MIGHT NOT BE RECOGNIZED AND DIAGNOSED IMMEDIATELY, CONGENITAL HYDROCEPHALUS IS OFTEN DIAGNOSED BEFORE BIRTH THROUGH ROUTINE ULTRASOUND. 4. ACQUIRED: ACQUIRED HYDROCEPHALUS DEVELOPS AFTER BIRTH AS A RESULT OF NEUROLOGICAL CONDITIONS THIS TYPE OF HYDROCEPHALUS CAN AFFECT INDIVIDUALS OF ALL AGES AND MAY BE CAUSED BY HEAD TRAUMA, BRAIN TUMOR, CYST, INTRA-VENTRICULAR HEMORRHAGE OR INFECTION OF THE CENTRAL NERVOUS SYSTEM.  MECHANISM OBSTRUCTION TO THE FLOW OF CSF EITHER IN THE VENTRICULAR SYSTEM OR IN THE SUBARACHNOID SPACE. BLOCKAGE OF CSF CAN BE CAUSED BY A VARIETY OF CONDITIONS SUCH AS BIRTH DEFECTS OF BRAIN, CERTAIN BRAIN INFECTIONS, HEMORRHAGE OR TUMORS.  THE BLOCKAGE CAN BE WITHIN THE VENTRICLES THEMSELVES OR OUTSIDE THE BRAIN. INCREASED SECRETION OF CSF AS OCCURS VERY RARELY WITH NEOPLASIA OF CHOROID PLEXUS THAT SECRETE CSF.  CSF - Obstruction of CSF pathway - Functional disturbance of CSF absorption - Excessive production of CSF Excessive accumulation Cerebral ventricles or subarachnoid space enlargement Head enlargement, Increasing ICP, Cerebral dysfunction  PATHOLOGY WHEN THE OBSTRUCTION OCCUR EARLY IN LIFE BEFORE FUSION OF CRANIAL SUTURES THE HEAD ENLARGES AND WORSE EFFECTS ON BRAIN OF INCREASED INTRACRANIAL PRESSURE ARE THEREFORE AVOIDED OR DELAYED. AFTER FUSION INCREASED INTRACRANIAL PRESSURE PRODUSES WORST EFFECT ON BRAIN.  LEARNING OUTCOMES IN THIS TOPIC WE HAVE LEARNT ABOUT HYDRONEPHROSIS AND ALSO ABOUT ITS CAUSES, PATHOPHYSIOLOGY AND RISK FACTORS. DISCUSSED ABOUT ITS COMPLICATIONS AND INVESTIGATIONS.  REFERENCES SHORT TEXT BOOK OF PATHOLOGY BY MOHAMMAD INAM DANISH. GENERAL PATHOLOGY BY FIRDAUS. PATHOLOGY-WIKIPIDEA